1. Field of the Invention
This invention relates to soap bars containing sugar surfactants and abrasives. More specifically, the present invention relates to soap bars containing sugar surfactants and abrasives.
2. Description of the Related Art
Soap in bar form has long been in use for cleansing purposes. Those skilled in the art use the term soap to designate the reaction product of a carboxylic acid with a base, typically a metal hydroxide or carbonate. The resulting salt has both a polar hydrophilic end and a non-polar lipophilic end which facilitates the removal of oils and other non-polar materials from the skin or other surface in the presence of water.
Bar soaps are customarily prepared either by framing/casting or by refining/plodding. Framed cast soaps are prepared by reacting an appropriate fat, oil or carboxylic acid with a base in the presence of water to form soap, pouring the molten soap containing about 30% water into a frame or a mold, allowing the soap to cool and harden, and removing the soap having about 20% to 25% water by weight in a bar form. Those skilled in the soap-making art are aware that the carboxylic acid hereafter referred to as a fatty acid is readily available as an article of commerce. The fatty acid also can be obtained from a fat, such as tallow or lard, from an oil, such as coconut oil, palm oil, palm kernel oil, or olive oil, or from combinations of fats and oils. Fats and oils are comprised in substantial part of glycerides of varying chain lengths, which are esters of glycerol (glycerine) and fatty acids. Under alkaline conditions, and in the presence of heat, the glycerides constituting the fats and oils break down to form fatty acid salts, also known as soaps, and glycerine.
Refined/plodded soap bars are produced by subjecting the neutralized soap to various finishing steps which alter the crystalline matrix of the soap from the omega phase, as formed in framed/cast soap bars, to the beta phase. A more detailed discussion may be found in Bailey's Industrial Oil And Fat Products, 4th ed., Vol. 1, p. 558 et seq. (1979). Prior to conversion the soap is first dried from a moisture level of approximately 30% to a level in the range of about 10% to about 14%. Next, the dried soap is generally sent to a simple paddle-type mixer where a variety of additives can be introduced. From this mixer the soap is then sent either directly to a refiner or optionally to a three-roll mill and then to the refiner. Both the refiner and the mill subject the soap to compression and an intense shearing action which tend to orient the soap crystals and convert the soap largely to the beta-phase. After refining, the soap is compressed into a dense, coherent form in a plodding operation which forms solid portions which are suitable for stamping into bars.
Soap bars useful for heavy duty personal cleansing such as for removing heavy soils such as oil, grease, clay and the like contain an abrasive such as pumice to mechanically assist the removal of such heavy soils. One drawback of these types of bars has been their poor lather characteristics, hand feel and skin care properties.